Dianjixueteng is a geoherb in Yunnan Province, the source plant of which is Kadsura interior. However, the formation of this geoherb is not clear in genetic mechanism, in which genome size is the first step that should be known on the genomic level. In this study we aimed to estimate the genome sizes of source plants of K. interior and three related herbs K. heteroclita, K. longipedunculata, and K. coccinea by flow cytometry (FCM) and make a comparison. The genome sizes of K. interior, K. heteroclita, K. longipedunculata and K. coccinea, i.e., the source plants of Dianjixueteng and its relative medicinal materials, were estimated by FCM. The nuclei of K. interior were isolated using modified LB01 buffer, for the rest species, by the Galbraith’s buffer. The genome sizes of K. interior, K. heteroclita, K. longipedunculata, and K. coccinea were 7.36, 7.12, 7.01, and 5.15 pg/1C, respectively. Genome size of K. interior had no significant variation with those of K. heteroclita and K. longipedunculata (P = 0.296), which was significantly larger than that of K. coccinea. Genome size can not distinguish K. interior from K. heteroclita and K. longipedunculata, but could distinguish them from K. coccinea, which lays the foundation for future studies on genetic mechanism of the geoherb formation.

Phellodendron amurense Rupr., a species of Rutaceae, is a nationally protected and valuable medicinal plant. It is generally considered to be dioecious. With the discovery of monoecious P. amurense, the phenomenon that its sex development is regulated by epigenetics has been revealed, but the way epigenetics affects the sex differentiation of P. amurense is still unclear. In this study, we investigated the effect of DNA methylation on the sexual development of P. amurense. The young inflorescences of male plants were treated with the demethylation agent 5-azaC, and the induced female flowers were obtained. The induced female flowers’ morphological functions and transcriptome levels were close to those of normally developed plants. Genes associated with the development of female flowers were studied by comparing the differences in transcriptome levels between the male and female flowers. Referring to sex-related genes reported in other plants, 188 candidate genes related to the development of female flowers were obtained, including sex-regulating genes, genes related to the formation and development of sexual organs, genes related to biochemical pathways, and hormone-related genes. RPP0W, PAL3, MCM2, MCM6, SUP, PIN1, AINTEGUMENTA, AINTEGUMENTA-LIKE6, AGL11, SEUSS, SHI-RELATED SEQUENCE 5, and ESR2 were preliminarily considered the key genes for female flower development. This study has demonstrated that epigenetics was involved in the sex regulation of P. amurense, with DNA methylation as one of its regulatory modes. Moreover, some candidate genes related to the sexual differentiation of P. amurense were obtained with analysis. These results are of great significance for further exploring the mechanism of sex differentiation of P. amurense and studying of sex differentiation of plants.

Viscum coloratum (Viscaceae) is a kind of semiparasitic shrub used as medicinal plant. The complete chloroplast (cp) genome of V. coloratum was sequenced and characterized in this study. Length of total cp genome is 128,744 bp, which is constructed by four typical regions including a large single-copy region (LSC, 73,684 bp), a small single-copy region (SSC, 8630 bp) and a pair of inverted-repeat regions (IRs, 23,215 bp). 100 unique genes are predicted including 68 protein-coding genes, 28 tRNA genes and four rRNA genes. Phylogenetic analysis were performed based on 30 shared genes of 12 species in Santalales using maximum likelihood method. The results showed a close relationship between V. coloratum and V. album. The complete cp genome of V. coloratum would provide valuable genetic resources for further study on phylogeny, population genetics and identification in Viscum.

Gray mold disease severely impacts the yield and quality of Panax notoginseng (Burkill) F. H. Chen ex C. Chow & W.G. Huang. In this study, a strain of Botrytis fabiopsis J. Zhang, G.N. Wu & G.Q. Li labeled as 3-3 was isolated from the leaves affected by gray mould disease of P. notoginseng, identified as a novel pathogen for this plant. Targeting the strain 3-3, an antagonistic bacterial strain X30 was isolated from the leaves of P. notoginseng and was preliminarily identified as Bacillus amyloliquefaciens (Fukumoto) Priest et al. through morphological and molecular biological analyses. The in vitro antifungal test showed that strain X30, at a concentration of 1 × 10⁸ CFU mL⁻¹, had an inhibition rate of 84.63% against the B. fabiopsis strain 3-3, and it exhibited broad-spectrum antifungal activity against other major pathogenic fungi of P. notoginseng, including Alternaria alternata (Fr.) Keissl., Rhizoctonia solani J.G. Kühn and others. Additionally, strain X30 was found to produce ammonia, fix nitrogen, secrete plant growth hormones, and release multiple hydrolytic enzymes, thus possessing both plant-growth-promoting and antimicrobial traits. In pot experiments, an X30 suspension at 1 × 10⁸ CFU mL⁻¹ achieved 61.04% control rate against B. fabiopsis. Using non-targeted metabolomics, compounds in the culture filtrate of strain X30 were analyzed, and two organic acid compounds with antimicrobial activity were identified. Among them, phenylpyruvic acid had an EC₅₀ value of 312 µg mL⁻¹ against pathogen 3-3, while 2,6-dihydroxybenzoic acid had an EC₅₀ value of 660 µg mL⁻¹. B. amyloliquefaciens X30 provides a theoretical basis for developing green and efficient biocontrol agents against gray mould in P. notoginseng.